xref: /openbmc/linux/drivers/mtd/maps/uclinux.c (revision 643d1f7f)
1 /****************************************************************************/
2 
3 /*
4  *	uclinux.c -- generic memory mapped MTD driver for uclinux
5  *
6  *	(C) Copyright 2002, Greg Ungerer (gerg@snapgear.com)
7  *
8  * 	$Id: uclinux.c,v 1.12 2005/11/07 11:14:29 gleixner Exp $
9  */
10 
11 /****************************************************************************/
12 
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/fs.h>
18 #include <linux/major.h>
19 #include <linux/mtd/mtd.h>
20 #include <linux/mtd/map.h>
21 #include <linux/mtd/partitions.h>
22 #include <asm/io.h>
23 
24 /****************************************************************************/
25 
26 struct map_info uclinux_ram_map = {
27 	.name = "RAM",
28 };
29 
30 struct mtd_info *uclinux_ram_mtdinfo;
31 
32 /****************************************************************************/
33 
34 struct mtd_partition uclinux_romfs[] = {
35 	{ .name = "ROMfs" }
36 };
37 
38 #define	NUM_PARTITIONS	ARRAY_SIZE(uclinux_romfs)
39 
40 /****************************************************************************/
41 
42 int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
43 	size_t *retlen, u_char **mtdbuf)
44 {
45 	struct map_info *map = mtd->priv;
46 	*mtdbuf = (u_char *) (map->virt + ((int) from));
47 	*retlen = len;
48 	return(0);
49 }
50 
51 /****************************************************************************/
52 
53 int __init uclinux_mtd_init(void)
54 {
55 	struct mtd_info *mtd;
56 	struct map_info *mapp;
57 	extern char _ebss;
58 	unsigned long addr = (unsigned long) &_ebss;
59 
60 	mapp = &uclinux_ram_map;
61 	mapp->phys = addr;
62 	mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(addr + 8))));
63 	mapp->bankwidth = 4;
64 
65 	printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n",
66 	       	(int) mapp->phys, (int) mapp->size);
67 
68 	mapp->virt = ioremap_nocache(mapp->phys, mapp->size);
69 
70 	if (mapp->virt == 0) {
71 		printk("uclinux[mtd]: ioremap_nocache() failed\n");
72 		return(-EIO);
73 	}
74 
75 	simple_map_init(mapp);
76 
77 	mtd = do_map_probe("map_ram", mapp);
78 	if (!mtd) {
79 		printk("uclinux[mtd]: failed to find a mapping?\n");
80 		iounmap(mapp->virt);
81 		return(-ENXIO);
82 	}
83 
84 	mtd->owner = THIS_MODULE;
85 	mtd->point = uclinux_point;
86 	mtd->priv = mapp;
87 
88 	uclinux_ram_mtdinfo = mtd;
89 	add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS);
90 
91 	return(0);
92 }
93 
94 /****************************************************************************/
95 
96 void __exit uclinux_mtd_cleanup(void)
97 {
98 	if (uclinux_ram_mtdinfo) {
99 		del_mtd_partitions(uclinux_ram_mtdinfo);
100 		map_destroy(uclinux_ram_mtdinfo);
101 		uclinux_ram_mtdinfo = NULL;
102 	}
103 	if (uclinux_ram_map.virt) {
104 		iounmap((void *) uclinux_ram_map.virt);
105 		uclinux_ram_map.virt = 0;
106 	}
107 }
108 
109 /****************************************************************************/
110 
111 module_init(uclinux_mtd_init);
112 module_exit(uclinux_mtd_cleanup);
113 
114 MODULE_LICENSE("GPL");
115 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
116 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
117 
118 /****************************************************************************/
119